The present invention relates to a vacuum cleaner hose manufactured by spirally winding and sticking a band-shaped material itself extruded with an electric wire inserted therein.
Generally, vacuum cleaner hoses are manufactured by inserting an electric wire into hollow protrusions of a band-shaped material extruded from dies to have concave cross-sections spaced at a given interval, and spirally winding the band-shaped material having the electric wire inserted in the hollow protrusions. This vacuum cleaner hose functions to apply an electric current to a motor.
Such vacuum cleaner hoses are broadly classified into two categories: a hose in which a two-strand electric wire is inserted in such a manner to operate only one motor to perform the fundamental function of sucking dust, foreign materials and the like; and a hose in which a four-strand electric wire is inserted in such a manner to operate two motors to perform water cleaning functions in addition to the fundamental function of sucking dust and foreign materials.
FIGS. 1 to 8 illustrate vacuum cleaner hoses according to the prior art.
FIG. 1 shows an illustrative process of forming a hose by spirally winding the band-shaped material 2 inserted with the four-strand electric wire 5.
As illustrated in various forms in FIGS. 2, 3, 4 and 5, the band-shaped material 2 for forming the hose 1 comprises one elevated hook 1, and two to four hollow protrusions connected to the hook 1. One or two electric wires 5 are inserted into each of the hollow protrusions 4, and in this state, the hollow protrusions 4 are connected to each other by the cover 3a having a similar shape to the hook 3.
Namely, FIG. 2 shows that the two-strand electric wire 5 is inserted into each of the hollow protrusions 4, FIG. 3 shows that the four-strand electric wire 5 is inserted into each of the hollow protrusions 4, and FIG. 4 shows that both two-strand electric wire 5 and the four-strand electric wire 5 are inserted into any one of the hollow protrusions 4.
And, FIG. 5 shows that two four-strand electric wires 5 are inserted into each of the hollow protrusions 4.
Each of the band-shaped materials 2 having the above described configurations is spirally wound so that the hook 3 located at one side of each of the band-shaped materials 2 covers the upper surface of the hollow protrusion 4 located at the other side while it is stuck to itself. As a result, as shown in FIGS. 6, 7 and 8, the vacuum cleaner hose 1 is manufactured in which one or two electric wires 5 is inserted in each of the hollow protrusions 4.
Namely, FIG. 6 shows the case where one electric wire 5 is inserted into each of the hollow protrusions 4, like the cases of FIGS. 2 and 3. FIG. 7 shows the case where two four-strand electric wires 5 are inserted into one of three hollow protrusions 4, and one four-strand electric wire 5 is inserted into each of the remaining two hollow protrusions 4, like the case of FIG. 4. FIG. 8 shows the case where two four-strand electric wires are inserted into each of two hollow protrusions 4, like the case of FIG. 4.
Accordingly, in the prior vacuum cleaner hoses as shown in FIGS. 1 to 8, one or two electric wires 5 are inserted into each of the protrusions wound over the full length, and thus, there is a problem in that they form an excessively dense and wasteful structure in view of the fact that the main function of the electric wires 5 is only to apply power to a motor.
Furthermore, since the electric wires 5 are made of expensive copper wires, the larger the amount of use of the electric wires 5, the higher the production cost of the resulting product. Thus, the prior vacuum cleaner hoses having an excessively dense structure have the problem of a reduction in economic efficiency above all things. Another problem is that the prior electric wires have a relatively high unit weight which makes their transport or handling inconvenient.